1. Field of the Invention
The present invention is generally related to meters, and more specifically, relates to a method and apparatus for providing security access for a communications board forming part of an energy meter.
2. Related Art
Electronic meters comprising energy registers and optical communications ports are well known in the art. Examples of reading/programming apparatus for reading information from and programming operation of electronic meter registers are set forth in U.S. Pat. Nos. 4,393,501, 4,491,791, 4,491,792 ; and 4,491,793. Examples of electronic registers are set forth in U.S. Pat. Nos. 4,571,692 and 4,465,970. Examples of electronic meters are set forth in U.S. Pat. No. 5,059,896.
Meter registers typically have a security code associated therewith. The security code, for example, is a predesignated number stored in the meter register memory. When a user tries to access the meter register data, the user must first transmit the proper security code. Upon receipt of a security code, e.g., a unique 80 bit code, the transmitted code is compared to the code stored in the register memory. If the transmitted and stored code match, the meter register will begin communications. If an invalid security code is received, the meter register will not communicate.
With the addition of a power line communications unit to an energy meter, it would be desirable to provide that both the communications unit and the meter register have the same security code. However, the register and communications unit must be able to distinguish between communications intended for the register and communications intended for the communication unit.